MiR-194 is involved in morphogenesis of spiral ganglion neurons in inner ear by rearranging actin cytoskeleton via targeting RhoB
MiR-194 is involved in morphogenesis of spiral ganglion neurons in inner ear by rearranging actin cytoskeleton via targeting RhoB
复制标题
MiR-194 通过靶向 RhoB 重新排列肌动蛋白细胞骨架，参与内耳螺旋神经节神经元的形态发生。
DOI：
10.1016/j.ijdevneu.2017.09.004
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发表时间：
2017-12-01
影响因子：
1.8
通讯作者：
Ba, Luo
中科院分区：
文献类型：
--
作者：
Du, Jintao;Zhang, Xuemei;Ba, Luo
许多microRNA参与胚胎和成人内耳的发育、分化和功能保存，但关于内耳中众多microRNA的许多细节仍需要阐明。基于先前对内耳microRNA谱的研究，我们证实了几种microRNA在内耳中表达，并且我们检测了这些microRNA在新生小鼠内耳中的空间表达。然后我们重点研究了miR-194在内耳发育过程中的特异性表达及其动态时空模式。在培养的螺旋神经节细胞中过表达miR-194显著影响了分化的神经元树突，具有更多的分支和明显分散的神经纤维。此外，培养细胞的细胞骨架受到显著影响，因为观察到由miR-194过表达引起的无序肌动蛋白丝和由miR-194敲低引起的增强丝。结合生物信息学方法，RT-qPCR和western blot结果显示RhoB是miR-194在螺旋神经节神经元形态发生中的候选靶点。此外，双荧光素酶报告系统用于鉴定RhoB作为miR-194的新靶点。最后，艰难梭菌毒素B对Rho B激活的抑制扰乱了肌动蛋白丝的组织，类似于miR-194过表达的作用。总之，我们研究了microRNA在小鼠内耳中的表达，并证明了miR-194在内耳发育过程中动态表达;重要的是，我们发现miR-194通过Rho B介导的F-actin重排积极影响神经元形态发生。
Many microRNAs participate in the development, differentiation and function preservation of the embryonic and adult inner ear, but many details still need to be elucidated regarding the numerous microRNAs in the inner ear. Based on previous investigations on the microRNA profile in the inner ear, we confirmed that several microRNAs are expressed in the inner ear, and we detected the spatial expression of these microRNAs in the neonatal mouse inner ear. Then we focused on miR-194 for its specific expression with a dynamic spatiotemporal pattern during inner ear development. Overexpression of miR-194 in cultured spiral ganglion cells significantly affected the dendrites of differentiated neurons, with more branching and obviously dispersed nerve fibres. Furthermore, the cytoskeleton of cultured cells was markedly affected, as disordered actin filaments resulting from miR-194 overexpression and enhanced filaments resulting from miR-194 knockdown were observed. Together with the bioinformatic methods, the RT-qPCR and western blot results showed that RhoB is a candidate target of miR-194 in the morphogenesis of spiral ganglion neurons. Additionally, the double luciferase reporter system was used to identify RhoB as a novel target of miR-194. Finally, the inhibition of RhoB activation by Clostridium difficile toxin B disturbed the organization of the actin filament, similar to the effects of miR-194 overexpression. In summary, we investigated microRNA expression in the mouse inner ear, and demonstrated that miR-194 is dynamically expressed during inner ear development; importantly, we found that miR-194 affects neuron morphogenesis positively through Rho B-mediated F-actin rearrangement.